The invention resides in an anchor for installation in lightweight construction panels including a support core with a first and a second cover plate and an anchor installation method with cement injection for form- and material-locking mounting of the anchor, which includes an expansion body embedded with a cement material.
Lightweight construction panels with support cores disposed between cover plates are often also called sandwich plates, honeycomb plates or light-weight construction panels. All types of panels used in furniture construction generally include cover plates or veneer of thin wood shaving plates, medium- or high-density fiber plates, plywood or hard fiber plates. The sandwich panels include as intermediate layer or support core for example polymethane foam or polysterol. In the honeycomb panels, often corrugated web inserts or so-called expanded honeycomb layers are used as intermediate support layers. Most lightweight panels have a raw density which is below 500 kg/m3. If for the intermediate layer no fire retardant aluminum foams or expanded glass is used, the raw density is below 350 kg/m3. For comparison, it is noted that the raw density of an unveneered particle board is about 600-750 kg/m3.
If hardware is to be attached to lightweight construction panels for example by screws, it is a problem that the mounting means generally find hold only on the relatively thin cover layers or cover plates. A typical solution herefor are straddling dowels as they are disclosed in the printed publication DE 20 2004 000 474 U1. The straddling dowels however have the disadvantage that they engage the upper cover plate in front and back over a large area. The rear engagement displaces furthermore the support core material over a large area around the bore whereby the cover plate is easily released from the support core material when a pulling force is effective on the straddling dowel.
Furthermore, from the brochure “Fischer Leichtbauplattenbefestiger” of the company Fischer Befestigungssysteme GmbH, a cement anchor is known since May 2007. The cement anchor is a tubular body which is provided at its upper end with a plurality of transverse bores which end in a kind of thread grooves. At its lower end, the body is open. The lower edge includes semi-circular channels. For mounting, the anchor is inserted into a bore in the lightweight construction panel—without mechanical fixing. Into the central bore of the tubular body, a cement material is pressed which exits the tubular body in the area of the cover plates. In the process, the cement material also fills the central bore of the anchor. The mounting element, for example a screw, is then screwed into the cement material in the central bore.
It is the object of the present invention to provide an anchor for lightweight construction panels, which can be easily installed into the lightweight construction panel and which is firmly and durably retained therein.